I want to run hello world written on C++ and compiled with Android toolchain 9, but I faced with issue: by default I have no permissions to launch it and I can't change permissions using chmod`.
I used Android 2.3.3 - Api Level 10
Application was compiled by cross compiler for API level 9
Procedure:
Compile application:
~/toolchain_andr9/bin/ arm-linux-androideabi-g++ helloworld.cpp
Then send application to SDCARD on the emulator:
>adb push a.out /mnt/sdcard
then go to SHELL and try to run a.out:
>adb shell
>
>/mnt/sdcard/a.out
And result is:
>`/mnt/sdcard/a.out: permission denied`
command ls -l shows rights for a.out:
>`----rwxr-x system sdcard_rw 863656 2012-04-12 22:42 a.out`
I tried to change permissions:
>chmod 777 /mnt/sdcard/a.out
But rights don't change:
>`----rwxr-x system sdcard_rw 863656 2012-04-12 22:42 a.out`
I think I have left some important thing using android.
Could anybody help me and give me a way how to run application in `Android SHELL?
Thanks a lot.
P.S. sorry for my English =)
By default, the SD card is mounted with option noexec, that disallows the execution of any file on the card, no matter what it's permissions(even -rwxrwxrwx), so you need to move the file to another location and then execute it.
The easiest is to move the file to /data/local/tmp/ and execute it using the full path (usual POSIX PATH semantics).
> adb push a.out /data/local/tmp/a.out
> adb shell
> chmod 755 /data/local/tmp/a.out
> /data/local/tmp/a.out
This does not require root access and survives reboot.
If you have rooted your phone you can do a mount -o remount,rw /mnt/sdcard and it should run.
I've tried it on my Android.
Related
How to know which Emulator image will contain su?
I can see that often it only contains su or google play
Run adb root and you get a root shell ... otherwise su needs to be manually installed.
However, when already having a root shell available, installing it isn't much of a problem.
All images are rooted, but SDK apps requesting escalation of privileges do rely upon su.
This question here generally duplicates: How to get root access on Android emulator?
adb shell scripting must:
start the emulator
run adb root
run adb shell
remount system partition
adb push the su binary
chmod to set permissions
exit
Or to answer the question:
start the emulator
and check if the file exists, eg. with adb shell stat /usr/bin/su
Where stat gives this response, when it's not installed:
stat: '/usr/bin/su': No such file or directory
One could even loop all Android images installed in $ANDROID_SDK_HOME...
there's no "one click" solution, but adb can be fully automated with Bash or Batch. And one wouldn't even have to run the emulator, but can mount QCOW2 as a nbd network block device.
This is fairly a very old question but I am surprised that none of the solutions are working for me. I need to run an android app as system app in an AVD (in emulator) created for Android version 7.0. For this, I want to push apk file to system partition but I keep getting error saying it is read only file system. I found many similar questions on stackoverflow but nothing is working for me. I restarted adb in root, executed it with remount as suggested in answers to similar questions, but system partition file system permissions do not change. Here is a sample session:
mvsagar#mvslt:~/sw/android_sdk/platform-tools$ ./adb root
restarting adbd as root
mvsagar#mvslt:~/sw/android_sdk/platform-tools$ ./adb remount
remount succeeded
mvsagar#mvslt:~/sw/android_sdk/platform-tools$ ./adb push /home/mvsagar/projects/AndroidStudioProjects/LcnApps/app/LCNUE.apk /system/app/LCNUE.apk
adb: error: failed to copy '/home/mvsagar/projects/AndroidStudioProjects/LcnApps/app/LCNUE.apk' to '/system/app/LCNUE.apk': couldn't create file: Read-only file system
I have tried manually remounting with read/write(rw) options using adb shell, but the remounting fails.
Is there any way to have read/write permission on system partition?
My dev env is Android Studio on Ubuntu.
In my case, I use a avd( Based on: Android 8.0 (Oreo) Tag/ABI: google_apis/x86_64 ).
$ emulator -avd Nexus_5X_API_26_APIs -writable-system
$ adb root
$ adb remount
Then, /system is writeable.
$ adb push somefile /system/bin/ is work.
When working with Q, this is the only solution that worked for me: https://stackoverflow.com/a/64397712/1898527
Adding here the steps for completion (kudos to the original author):
> emulator -avd Pixel_3a_XL_API_29 -writable-system
> adb shell avbctl disable-verification
> adb disable-verity
Now reboot your emulator so that the changes take effect.
> adb root
> adb remount
> adb shell "su 0 mount -o rw,remount /system"
Note: you will need an emulator without Google Play, otherwise this won't work. You can get it by following the steps described here: https://stackoverflow.com/a/45668555/1898527
use genymotion emulator, which is faster, light weight and pre rooted. (which means you can access system directory)
For the benefit of others, answer to the question was answered a long ago by #Ishamael in another stackoverflow question Read only file system on Android
I'm trying to use the Android Adb Command Prompt to copy a folder inside the app container to a local Windows folder. The device is running Android 5.1.1 and is not rooted.
adb pull or cp aren't working. How can I copy a folder?
The following approaches aren't working:
Approach 1
adb shell
adb pull /data/data/DroidSample.DroidSample/files/MetroLog/MetroLogs C:/temp/test
error: device not found
Inside the shell you can't see to do adb pull. See here.
Approach 2
DDMS can't access the data folder.
Approach 3
adb shell
run-as DroidSample.DroidSample
cp /files/MetroLog/MetroLogs/ C:/temp/test
cp: /files/MetroLog/MetroLogs/: No such file or directory
Approach 4
adb shell
run-as DroidSample.DroidSample
cp /data/data/DroidSample.DroidSample/files/MetroLog/MetroLogs/ C:/temp/test
cp: /data/data/DroidSample.DroidSample/files/MetroLog/MetroLogs is a directory (not copied).
This is also not working.
Approach 5
adb shell
run-as DroidSample.DroidSample
chmod 777 /files/MetroLog/MetroLogs
exit
exit
adb pull /data/data/DroidSample.DroidSample/files/MetroLog/MetroLogs C:/temp/test
adb shell run-as DroidSample.DroidSample
chmod 700 /files/MetroLog/Metrologs
remote object '/data/data/DroidSample.DroidSample/files/MetroLog/MetroLogs' does not exist
So also this isn't working.
Approach 6
adb shell
mkdir /sdcard/tmp
cp /data/data/DroidSample.DroidSample/files/MetroLog/MetroLogs /sdcard/tmp
cp: /data/data/DroidSample.DroidSample/files/MetroLog/MetroLogs: Permission denied
This is also not working.
Approach 7
The only thing which half work is this
adb exec-out run-as DroidSample.DroidSample cat "files/MetroLog/MetroLogs/Log - 20160509.log" > C:/temp/test/test.log
But here I don't get the original file and I also have to know the exact file name. Additionally, that I loose line breaks and I have to do this for each file. Not that what I want.
So I'm running out of ideas. How can I access the internal stored files and copy them over?
You have almost solved the problem. As the storage of this kind is secured, you need to do one additional step. You need to copy the file from secured location to sdcard of the device. And then you can copy it anywhere via usb or android pull. Here are the command sequence I executed successfully.
adb shell
run-as DroidSample.DroidSample
cd shared_prefs
cp DroidSample.DroidSample_preferences.xml /sdcard/DroidSample.DroidSample_preferences.xml
exit
exit
adb pull /sdcard/DroidSample.DroidSample_preferences.xml C:/test/
That's it.
And I really appreciate the way you posted your question. Best of luck.
You're trying to gain read access to /data partition on actual android device. Such thing is not possible without root access, even if the app folder is yours. For the reason that permissions to read /data partition are not granted and cannot be granted, unless you're using an emulator. On emulator, which by default is with admin privileges for developer, you can access the data partition to read and write. On actual device you cannot. Not with adb, not with DDMS.
So basically speaking, anything that requires access to those files under /data is not going to work. Whether you sue cp command or pull command. The moment your kernel reads the beginning of your path which starts with /data/... it says: Oops, no can do.
You are trying to access /data folder of android device which is not accessible in unrooted device.
Do I actually need to root my phone to run a program that prints hello world?
I am trying to run a binary file after I have cross compiled it.
I get permission denied when I push the file into /data/local/tmp directory.
Any ideas where I should push it so that it can run? If possible?
Or do I need to try it on Terminal Emulator?
No, you don't need to have root permissions to run executable on Android.
Most likely, after pushing file to /data/local/tmp, it have no required permissions - that's why you got "permission denied". Do it as following:
adb push /path/to/executable /data/local/tmp
adb shell chmod 0755 /data/local/tmp/executable
adb shell 'cd /data/local/tmp && ./executable'
It works for me.
Do I actually need to root my phone to run a program that prints hello world?
No.
I get permission denied when I push the file into /data/local/tmp directory.
Perform a chmod a+x after you push it. I seem to recall the Android runtime does not understand octal. (Or maybe its the other way around based on #crystax's answer).
I am searching for the equivalent Linux command of following Android adb shell command:
%ANDROID%\platform-tools\adb.exe shell ^
/system/bin/chmod 0777 /data/local/asl-native
This will be used to give the read and write permissions for a particular directory or file.
I have tried with the following Linux commands:
/system/bin/chmod u+rw /data/local/filename
However, it appears the file is not given permissions.
Most Android systems do not let you run as super user (i.e. root) and without that privilege, you cannot make this work.
You can read more bout how file storage works on Android here.